# Source code for nacl.encoding

    # Copyright 2013 Donald Stufft and individual contributors
    #
    # Licensed under the Apache License, Version 2.0 (the "License");
    # you may not use this file except in compliance with the License.
    # You may obtain a copy of the License at
    #
    # http://www.apache.org/licenses/LICENSE-2.0
    #
    # Unless required by applicable law or agreed to in writing, software
    # distributed under the License is distributed on an "AS IS" BASIS,
    # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    # See the License for the specific language governing permissions and
    # limitations under the License.
    import base64
    import binascii
    from abc import ABCMeta, abstractmethod
    from typing import SupportsBytes, Type

    # TODO: when the minimum supported version of Python is 3.8, we can import
    # Protocol from typing, and replace Encoder with a Protocol instead.
    class _Encoder(metaclass=ABCMeta):
        @staticmethod
        @abstractmethod
        def encode(data: bytes) -> bytes:
            """Transform raw data to encoded data."""

        @staticmethod
        @abstractmethod
        def decode(data: bytes) -> bytes:
            """Transform encoded data back to raw data.

            Decoding after encoding should be a no-op, i.e. `decode(encode(x)) == x`.
            """

    # Functions that use encoders are passed a subclass of _Encoder, not an instance
    # (because the methods are all static). Let's gloss over that detail by defining
    # an alias for Type[_Encoder].
    Encoder = Type[_Encoder]

    class RawEncoder(_Encoder):
        @staticmethod
        def encode(data: bytes) -> bytes:
            return data

        @staticmethod
        def decode(data: bytes) -> bytes:
            return data

    class HexEncoder(_Encoder):
        @staticmethod
        def encode(data: bytes) -> bytes:
            return binascii.hexlify(data)

        @staticmethod
        def decode(data: bytes) -> bytes:
            return binascii.unhexlify(data)

    class Base16Encoder(_Encoder):
        @staticmethod
        def encode(data: bytes) -> bytes:
            return base64.b16encode(data)

        @staticmethod
        def decode(data: bytes) -> bytes:
            return base64.b16decode(data)

    class Base32Encoder(_Encoder):
        @staticmethod
        def encode(data: bytes) -> bytes:
            return base64.b32encode(data)

        @staticmethod
        def decode(data: bytes) -> bytes:
            return base64.b32decode(data)

    class Base64Encoder(_Encoder):
        @staticmethod
        def encode(data: bytes) -> bytes:
            return base64.b64encode(data)

        @staticmethod
        def decode(data: bytes) -> bytes:
            return base64.b64decode(data)

    class URLSafeBase64Encoder(_Encoder):
        @staticmethod
        def encode(data: bytes) -> bytes:
            return base64.urlsafe_b64encode(data)

        @staticmethod
        def decode(data: bytes) -> bytes:
            return base64.urlsafe_b64decode(data)

    class Encodable:
        def encode(self: SupportsBytes, encoder: Encoder = RawEncoder) -> bytes:
            return encoder.encode(bytes(self))